2-6. Army support of civil authorities is a vital element of unified land operations and homeland security. However, DSCA tasks differ substantially from other elements of decisive action. Decisive action is the continuous, simultaneous execution of offensive, defensive, and stability operations or defense support of civil authorities tasks (ADP 3-0). Important differences include the roles and responsibilities of civilian organizations and the relationship of military forces to federal, state, territorial, tribal, and local government agencies. The purposes and characteristics of Army support in the homeland shape the Army's conduct of decisive action.